Upside Down Pizza

Preheat oven to 375 degrees. Combine mushrooms, bell pepper and olives in a large skillet. Cook 3 to 4 minutes until bell pepper is softened. Spread vegetables evenly in the bottom of a 9x13 inch baking dish. Add beef and onion to skillet. Cook 8 to 10 minutes, stirring frequently, until beef is browned, breaking up clumps. Drain well. Stir in tomato sauce, garlic powder and spaghetti sauce mix. Heat to a boil. Reduce heat and simmer 5 minutes. Spoon beef mixture over vegetables in dish. Sprinkle mozzarella evenly over beef. Unroll pizza dough over top of mozzarella. Bake 25 minutes. Let stand 5 minutes before cutting and serving.